Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China.
Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; National Engineering Research of Water Resources Efficient Utilization and Engineering Safety, Hohai University, Nanjing, 210098, China.
Environ Res. 2021 Mar;194:110733. doi: 10.1016/j.envres.2021.110733. Epub 2021 Jan 9.
Perfluoroalkyl acids (PFAAs) are ubiquitous in various environments. This has caused great public concern, particularly in the shallow freshwater lake region, where the lake, rivers, and estuaries form a highly interconnected continuum. However, little is known about the environmental behaviors of PFAAs in the continuum. For the first time, a high-resolution monitoring framework covering the river-estuary-lake continuum of Luoma Lake was built, and the concentrations, sources, and environmental fates of PFAAs were identified and analyzed. The results revealed that the total concentration of PFAAs was at a moderate level in the water and at a high level in the sediment compared to global levels respectively. Perfluorooctanesulfonate (PFOS) was the most abundant PFAA in the continuum. In particular, the ∑PFAA concentration in the particle phase was much higher than that in the sediment phase. Distinct spatial heterogeneities were observed in the behaviors of distribution and the multiphase fate of PFAAs in the continuum, mainly driven by the turbulent mixing during transport, dilution of lake water, and spatial differences of hydrodynamic features and sedimentary properties among the sub-regions. Interestingly, the pH of the sediment and water had significant effects on the water-sediment portioning of PFAAs in contrasting ways. Furthermore, based on the composition of the sediments, four possible migration paths for PFAAs were deduced and the main sources of PFAAs were identified as sewage, domestic, and industrial effluents using the positive matrix factorization model. During the human health assessment, no risk was found under the median exposure scenario; however, under the high exposure scenario, PFAAs posed uncertain risks to human health, which cannot be ignored. This study provides basic information for simulating the fate and transport of PFAAs in the continuum and is significant for developing cost-effective control and remediation strategies in the near future.
全氟烷基酸（PFAAs）广泛存在于各种环境中。这引起了公众的极大关注，特别是在浅水湖泊地区，那里的湖泊、河流和河口形成了一个高度相互关联的连续体。然而，人们对 PFAAs 在连续体中的环境行为知之甚少。本研究首次构建了一个涵盖骆马湖河流-河口-湖泊连续体的高分辨率监测框架，识别和分析了 PFAAs 的浓度、来源和环境归宿。结果表明，与全球水平相比，水相中 PFAAs 的总浓度处于中等水平，而沉积物中的浓度则处于较高水平。全氟辛烷磺酸（PFOS）是连续体中最丰富的 PFAAs。特别是，颗粒相中∑PFAA 的浓度远高于沉积物相中的浓度。在连续体中，PFAAs 的分布和多相归宿行为表现出明显的空间异质性，主要受输运过程中的紊流混合、湖水稀释以及亚区之间水动力特征和沉积物性质的空间差异的驱动。有趣的是，沉积物和水的 pH 值以不同的方式对 PFAAs 的水-沉积物分配具有显著影响。此外，基于沉积物的组成，推断出 PFAAs 可能存在四种迁移路径，并通过正定矩阵因子模型确定了 PFAAs 的主要来源为污水、生活和工业废水。在人体健康评估中，在中位数暴露情景下未发现风险；然而，在高暴露情景下，PFAAs 对人体健康构成了不确定的风险，不容忽视。本研究为模拟连续体中 PFAAs 的归宿和迁移提供了基础信息，对未来开发经济有效的控制和修复策略具有重要意义。
